Evaluation of the Brewing Characteristics, Digestion Profiles, and Neuroprotective Effects of Two Typical Se-Enriched Green Teas

Selenium-enriched green tea extracts: chemical constituents and effects on antioxidant and anti-inflammatory factors and four major intestinal flora in mice with intestinal disorders

BACKGROUND

Selenium-enriched tea represents an ideal source of selenium supplements, yet its effects on mice with intestinal disorders remain under-documented. Therefore, we have carried out relevant research.

METHODS

We determined the main chemical components of selenium-enriched green tea and evaluated the antioxidant and anti-inflammatory effects of selenium-enriched green tea extract and changes in intestinal flora of antibiotic-induced intestinal disease mice through BALB/c mouse experiments.

RESULTS

The main chemical components of selenium-enriched green tea and green tea are significantly different. Selenium-enriched green tea is characterized by a high selenium content, with tea polyphenols, flavonoids, tea polysaccharides and catechins being the primary constituents. The results of animal experiments indicate that the extract of green tea rich in selenium increased the content of antioxidant factors in the intestines of mice and reduced the levels of intestinal inflammatory factors. This was also confirmed by mRNA gene expression determination. In addition, selenium-enriched green tea extracts can reduce the weight loss and intestinal pathological damage induced by antibiotics, promote the colonization of Bifidobacterium and Lactobacillus in the intestinal tract of mice and inhibit the growth of Escherichia coli and Enterococcus in the intestinal tract.

CONCLUSION

Selenium-enriched green tea has high nutritional content. It demonstrates superior potential in alleviating oxidative stress and inflammatory responses caused by intestinal diseases, and plays a role in regulating the intestinal flora. © 2025 Society of Chemical Industry.

Insight into the effect of cultivar and altitude on the identification of EnshiYulu tea grade in untargeted metabolomics analysis

The accurate identification of tea grade is crucial to the quality control of tea. However, existing methods lack sufficient generalization ability in identifying tea grades due to the effect of temporal and spatial factors. In this study, we analyzed the effect of cultivar and altitude on EnshiYulu (ESYL) tea grades and established a robust model to evaluate their quality. Principal component analysis (PCA) revealed that differences in variety and elevation can mask grade differences. Orthogonal projection to latent structure-discriminant analysis (OPLS-DA) was used for grade identification of samples from different altitudes. For ESYL tea samples above and below 800 m altitude, 75 and 35 grade differentiated metabolites were discovered, with 14 common differentiated metabolites. Based on reconstructed OPLS-DA models, the grades of multi-altitude sources ESYL were discriminated with a rate > 85%. These results demonstrate the potential of a grade discrimination model based on common differential metabolites, which exhibits generalization ability.

Catechins and Selenium Species-How They React with Each Other

The combination of selenium and tea infusion, both with antioxidant properties, has potentially complementary mechanisms of action. Se-enriched tea has been considered as a possible Se supplement and a functional beverage to reduce the health risk of Se deficiency. This work investigated the interactions between plant catechins present in tea infusions and selenium species based on changes in the concentration of both reagents, their stability in aqueous solutions, and the possibilities of selenonanoparticles (SeNPs) formation. Selenium species exhibited instability both alone in their standard solutions and in the presence of studied catechins; selenocystine appeared as the most unstable. The recorded UV-Vis absorption spectra indicated the formation of SeNPs in the binary mixtures of catechins and selenite. SeNPs have also formed with diameters smaller than 100 nm when selenite and selenomethionine were added to tea infusions. This is an advantage from the point of view of potential medical applications.

Characterization of aroma compounds in Rosa roxburghii Tratt using solvent-assisted flavor evaporation headspace-solid phase microextraction coupled with gas chromatography-mass spectrometry and gas chromatography-olfactometry

Rosa roxburghii Tratt (RRT) has become popular owing to its high vitamin C content. Volatiles are important factors that affect the quality of RRTs and their processed products. In this study, volatile compounds were extracted using headspace-solid phase microextraction (HS-SPME) and solvent-assisted flavor evaporation (SAFE); 143 volatile compounds were identified by gas chromatography-mass spectrometry (GC-MS), and RRT from different origins were well distinguished based on principal component analysis. 45 odor-active components were identified using gas chromatography-olfactometry (GC-O). Through quantitative descriptive analysis (QDA), there were prominent "grassy" and "tea-like" attributes in RRT. Partial least-squares regression (PLSR) revealed that Longli RRT was greatly related to "tea-like" and "woody" attributes. Among the volatiles identified, alcohols and esters were considered the dominant volatile compounds of RRT, 4-methoxy-2,5-dimethyl-3(2H)-furanone was the most prominent compound. This study enriches the flavor chemistry theory of RRT and provides a scientific basis for optimizing the aroma of RRT and its processed products.

Correction: Ye et al. Evaluation of the Brewing Characteristics, Digestion Profiles, and Neuroprotective Effects of Two Typical Se-Enriched Green Teas. Foods 2022, 11, 2159

The authors wish to make the following corrections to their published paper [...]

Insights into the key quality components in Se-Enriched green tea and their relationship with Selenium

Selenium-enriched green tea (Se-GT) is of increasing interest because of its health benefits, but its quality components obtained limited research. In this study, Enshi Se-enriched green tea (ESST, high-Se green tea), Pingli Se-enriched green tea (PLST, low-Se green tea), and Ziyang green tea (ZYGT, common green tea) were subjected to sensory evaluation, chemical analysis, and aroma profiling. Chemical profiles in Se-GT were consistent with the taste attributes of the sensory analysis. 9 volatiles were identified as key odorants of Se-GT based on multivariate analysis. Correlations between Se and quality components were further assessed and highly Se-related compounds contents in these three tea samples were compared. The results showed that most amino acids and non-gallated catechins were highly negatively correlated with Se, while gallated catechins exhibited strong positive correlation with Se. And there were strong and significant associations between the key aroma compounds and Se. Moreover, 11 differential markers were found between Se-GTs and common green tea, including catechin, serine, glycine, threonine, l-theanine, alanine, valine, isoleucine, leucine, histidine, and lysine. These findings provide great potential for quality evaluation of Se-GT.

Electrospray-Assisted Fabrication of Dextran-Whey Protein Isolation Microcapsules for the Encapsulation of Selenium-Enriched Peptide

Selenium-enriched peptide (SP, selenopeptide) is an excellent organic selenium supplement that has attracted increasing attention due to its superior physiological effects. In this study, dextran-whey protein isolation-SP (DX-WPI-SP) microcapsules were fabricated via high-voltage electrospraying technology. The results of preparation process optimization showed that the optimized preparation process parameters were 6% DX (w/v), feeding rate Q = 1 mL/h, voltage U = 15 kV, and receiving distance H = 15 cm. When the content of WPI (w/v) was 4-8%, the average diameter of the as-prepared microcapsules was no more than 45 μm, and the loading rate for SP ranged from ~46% to ~37%. The DX-WPI-SP microcapsules displayed excellent antioxidant capacity. The thermal stability of the microencapsulated SP was improved, which was attributed to the protective effects of the wall materials for SP. The release performance was investigated to disclose the sustained-release capacity of the carrier under different pH values and an in-vitro-simulated digestion environment. The digested microcapsule solution showed negligible influence on the cellular cytotoxicity of Caco-2 cells. Overall, our work provides a facile strategy of electrospraying microcapsules for the functional encapsulation of SP and witnesses a broad prospect that the DX-WPI-SP microcapsules can exhibit great potential in the food processing field.